A hard coating film has been used for protecting the surface of various image displays including a liquid crystal display device (LCD), an electroluminescence (EL) display device, a plasma display (PD), a field emission display (FED) and the like.
Recently, a flexible display device which can maintain display performance even when it is bent like a paper by using a flexible material such as plastic, instead of a conventional glass substrate having no flexibility, gains attention as a next generation display device. In this regard, there is a need for a hard coating film which not only has high hardness and good scratch resistance but also has proper flexibility so that cracks do not occur, without curling at the film edges during its production or use.
Korean Patent Application Publication No. 10-2013-0135151 discloses a high-hardness hard coating composition including: a binder containing a tri-functional to hexa-functional acrylate-based monomer, inorganic fine particles, a photoinitiator, and an organic solvent.
However, such a high-hardness hard coating composition has a problem that bending resistance is lowered and curling occurs after curing.